﻿using System;
using System.Text;

static class StringBuilderExtensions
{
    public static StringBuilder Substring (this StringBuilder item,int start,int length)
    {
        StringBuilder result;
        result = new StringBuilder(length);
        for (int i = 0; i < length; i++)
        {
            result.Append(item[start + i]);
        }
        return result;
    }

    //static void Main(string[] args)
    //{
    //    StringBuilder test = new StringBuilder("Ninjas are stealthy.");
    //    StringBuilder result = test.Substring(0, 6);
    //    Console.WriteLine(result.ToString());
    //}
}
